Tuopangou Fm

The original Tuopangou Formation is dated to Early Jurassic; In 1978, the Stratigraphic Table Compilation Group in Jilin province was classified as the lower middle Jurassic. In 1988, Wu Shuibo et al. reclassified the original Tuopangou Formation into three groups, from the bottom to the top, the Tuopangou Fm, Sanxianling Fm and Malugou Fm are determined, clarified Tuopangou Formation is equivalent to be the lower part of the original Tuopangou Formation, which is neutral volcanic rock strata without fossils, and is dated to the Late Triassic. In 1982, Peng Yujing et al. subsumed the Tuopangou Formation into the Daxinggou Gr, dated to the Late Triassic. In 1991, Bureau of Geology & Mineral resources of Jilin province divided the Tuopangou Formation into upper and lower members. Indicated as Carnian on schematic stratigraphic section.